The present invention relates to the electrochemical generation of power and, more specifically, to electrochemical fuel cells where diluting gases migrate from the cathode side of the cell's membrane electrode assembly to the anode side of the cell's membrane electrode assembly. For example, by way of illustration and not limitation, where oxygen from air is used as a cathode-side reactant in a fuel cell and hydrogen is used as the anode-side reactant in the fuel cell, the partial pressure of nitrogen in the air drives nitrogen through the membrane electrode assembly from the cathode side to the anode side, diluting the hydrogen fuel on the anode side of the fuel cell and leading to poor fuel cell performance.